Technical Field
[0001] The present invention relates to an absorbent article.
Background Art
[0002] Conventionally, as absorbent articles such as a sanitary napkin, a panty liner, and
an incontinence pad, a structure is known in which an absorbent body is disposed between
a liquid-permeable topsheet, and a liquid-impermeable backsheet. Among such absorbent
articles, an absorbent article having an increased fittability in a region starting
from a part corresponding to a body fluid discharge opening to a rear part to prevent
leaks of the body fluid from the rear part is known.
[0003] For example, Patent Literature 1 discloses an absorbent article in which each of
side regions on both sides of an intermediate central region has lower stiffness than
side regions of a front central region and a rear central region.
[0004] Patent Literature 2 discloses a structure including arc-like embosses corresponding
to deformation of buttocks formed on both sides of a longitudinal central line, each
arc having a center of curvature outside of the absorbent article in a width direction;
and an emboss corresponding to an intergluteal cleft having an inverted V-shaped portion,
the inverted V-shape starting from the position on the longitudinal central line rearwardly
gradually diverging to both sides.
Citation List
Patent Literature
[0005]
Patent Literature 1: Japanese Patent No. 4323786
Patent Literature 2: Japanese Laid-open Patent Publication No. 2011-156070
Summary of Invention
Technical Problem
[0006] In Patent Literature 1, it is described that the disclosed structure enables the
front part and the rear part of the absorbent article to move individually following
the movement of a body. Further, in Patent Literature 2, it is described that the
absorbent article can be fitted corresponding to deformation of buttocks during sleeping
time.
[0007] However, in the absorbent articles disclosed in Patent Literatures 1 and 2, a scope
for improvement is associated with a more appropriate deformation to adapt to the
shape of the intergluteal cleft.
[0008] In light of the above, an object of the present invention is to provide an absorbent
article which is well deformable following the shape of the intergluteal cleft, and
thereby preventing leakage in the rear region of the absorbent article.
Solution to Problem
[0009] A first embodiment of the present invention provides an absorbent article including
a main body including a liquid-permeable topsheet, a liquid-impermeable backsheet,
and an absorbent body disposed between the topsheet and the backsheet, wherein the
main body has an elongated shape with a predetermined length in the front-rear direction
and a predetermined width in a width direction orthogonal to the front-rear direction,
and includes a compressed groove recessed from a topsheet side toward a backsheet
side, wherein the compressed groove includes a pair of front-rear direction compressed
grooves extending in the front-rear direction, wherein the front-rear direction compressed
grooves each include high-compressed portions and a low-compressed portion that is
less deeply recessed than the high-compressed portions, and each include a first rear
compressed groove formed in a region corresponding to an intergluteal cleft of a wearer
when attached, and a middle compressed groove formed forward of the first rear compressed
groove, and wherein a total area per unit length in the front-rear direction of the
high-compressed portions in the first rear compressed groove is smaller than a total
area per unit length in the front-rear direction of the high-compressed portions in
the middle compressed groove.
Advantageous Effects of Invention
[0010] According to one embodiment of the present invention, there is provided an absorbent
article which is well deformable following the shape of the intergluteal cleft, thereby
preventing leakage in the rear part.
Brief Description of Drawings
[0011]
FIG. 1 is a partially cutaway view showing an absorbent article according to one embodiment
of the present invention.
FIG. 2 is a cross-sectional view taken along the line IV-IV in FIG. 1.
FIG. 3A is a view illustrating deformation of an intergluteal cleft corresponding
region in an absorbent article according to an embodiment of the present invention
when attached.
FIG. 3B is a view illustrating deformation of an intergluteal cleft corresponding
region in an absorbent article according to the prior art when attached.
FIG. 4A is an enlarged view showing a middle compressed groove in an embodiment of
the present invention.
FIG. 4B is an enlarged view showing a first rear compressed groove in an embodiment
of the present invention.
FIG. 4C is an enlarged view showing a second rear compressed groove in an embodiment
of the present invention.
FIG. 5 is a view of an absorbent article according to another embodiment of the present
invention.
Description of Embodiments
[0012] An embodiment of the present invention will now be described with reference to the
drawings.
[0013] FIG. 1 is a partially cutaway view of an absorbent article 1 according to an embodiment
of the present invention. FIG. 2 is a cross-sectional view taken along IV-IV line
in FIG. 1. As shown in FIGs. 1 and 2, the absorbent article 1 includes a main body
(absorbent article main body) 8 including a liquid-impermeable backsheet 2, a liquid-permeable
topsheet 3, and an absorbent body 4 disposed between the backsheet 2 and the topsheet
3. The absorbent body 4 may be wrapped by an enveloping sheet made of crepe paper,
nonwoven fabric, or the like, for the purpose of maintaining a shape of the absorbent
body 4, etc.
[0014] As shown in FIG. 1, the main body 8 has an elongated shape in its entirety with a
predetermined length in a front-rear direction and a substantially constant width
in a direction orthogonal to the front-rear direction. In the illustrated embodiment,
the absorbent article 1 has a substantially line-symmetric shape with respect to a
centerline CL extending in the front-rear direction. However, the structure (including
the shape) of the absorbent article 1 or the main body 8 is not necessarily line-symmetric.
Further, the absorbent article 1 may have wings W, W to ensure a reliable fixation
of the absorbent article 1 to underwear when attached. In the illustrated example,
the wings W, W extend from each side of a region of the main body 8 including a site
corresponding to a body fluid discharge opening (body fluid discharge opening corresponding
portion) 40. However, the absorbent article 1 may not necessarily have wings W, W.
[0015] At the front and rear end portions of the absorbent body 4, the outer edges of the
backsheet 2 and the topsheet 3 are bonded to each other by an adhesive such as a hot-melt
adhesive, or by bonding means such as a heat seal, and an ultrasonic seal. Further,
a side nonwoven fabric 7 is arranged along the front-rear direction (longitudinal
direction) on each of the lateral parts on the topsheet side. The side nonwoven fabric
7 is partially protruded laterally from the main body 8, and laminated to the backsheet
2, which is also protruded laterally from the main body 8, by an adhesive such as
a hot-melt adhesive, or bonding means such as a heat seal, and an ultrasonic seal,
thereby forming the wings W, W on the both lateral sides of the main body 8.
[0016] The backsheet 2 may be made of a sheet material having at least water-blocking properties.
For example, an olefin resin sheet such as polyethylene or polypropylene may be used.
A laminated nonwoven fabric, which is formed by laminating a nonwoven fabric on a
polyethylene sheet or the like, or a laminated sheet of nonwoven fabric layers, which
has a waterproof film interposed therein to secure substantial liquid-impermeability
may be used. Further, a moisture-permeable sheet is preferably used in order to prevent
stuffiness. An example of such water-impermeable/moisture-permeable sheet material
includes a microporous sheet formed by melt-kneading an olefin resin such as polyethylene
or polypropylene with an inorganic filler to form a sheet, and then stretching the
sheet in a uniaxial direction or biaxial directions.
[0017] The topsheet 3 is a liquid-permeable sheet that allows quick passage of body fluid
such as menstrual blood, vaginal discharge, or urine. As the topsheet 3, a porous
or nonporous nonwoven fabric or a porous plastic sheet is preferably used. Examples
of fiber materials for the nonwoven fabric include synthetic fibers of an olefin such
as polyethylene or polypropylene, a polyester, a polyamide, or the like; regenerated
fibers such as rayon and cupra; blended fibers of these; and natural fibers such as
cotton. These fibers may be used alone or in any combination. Further, methods of
processing the nonwoven fabric may include spunlacing, spunbonding, thermal bonding,
melt blowing, and needle punching. Among these processing methods, the spunlacing
is preferable in being capable of manufacturing a nonwoven fabric with good flexibility,
the spunbonding is preferable in being capable of manufacturing a nonwoven fabric
with good drapability, and the thermal bonding is preferable in being capable of manufacturing
a bulky, soft nonwoven fabric. Further, composite fibers such as sheath-core fibers
having a high melting point fiber as a core and a low melting point fiber as a sheath,
side-by-side fibers, and split fibers may be used.
[0018] The material for the absorbent body 4 interposed between the backsheet 2 and the
topsheet 3 is not particularly limited as long as being capable of absorbing and retaining
body fluids, but for example, the absorbent member preferably includes cotton-like
pulp and a water absorptive polymer. Examples of the water absorptive polymer may
include superabsorbent polymer (SAP), superabsorbent fiber (SAF), and combinations
thereof. Examples of pulp include cellulose fibers such as chemical pulp obtained
from wood, dissolving pulp, and the like, and also artificial cellulose fibers such
as rayon, and acetate. Hardwood materials, softwood materials, and the like may be
used as the raw material for the chemical pulp, but the softwood materials are preferably
used due to their long fiber length, etc.
[0019] A synthetic fiber may be mixed in the absorbent body 4. Examples of the synthetic
fiber may include polyolefins such as polyethylene and polypropylene, polyesters such
as polyethylene terephthalate, and polybutylene terephthalate, polyamides such as
nylon, and copolymers thereof. Two or more of these materials may also be used in
mixture. Also, multi-component fibers such as sheath-core fibers having a core fiber
with a high melting point and a sheath fiber with a low melting point, side-by-side
fibers, split fibers, and the like may also be used. Hydrophobic fiber subjected to
a surface treatment with a hydrophilizing agent to exhibit affinity to body fluid
may be used.
[0020] The thickness of the absorbent body 4 is within the range from 0.5 mm to 25 mm, preferably
within the range from 3.5 mm to 7.5 mm. The absorbent body 4 may not necessarily have
a uniform thickness across its entire surface. For example, the absorbent body 4 may
have a bulging in the body fluid discharge opening corresponding portion 40 and the
vicinity thereof, or in the portion corresponding to the intergluteal cleft (intergluteal
cleft corresponding portion) and the vicinity thereof. Further, the absorbent body
4 is preferably manufactured by a stacking process or an air laid process.
[0021] Examples of the material that may be used as the side nonwoven fabric 7 include a
water-repellent treated nonwoven fabric, and a hydrophilically treated nonwoven fabric.
For example, for enhancing the anti-permeation effect against menstrual blood, vaginal
discharge, or the like, or improving the feel of texture, a water-repellent treated
nonwoven fabric coated with a silicone, paraffin, or alkyl chromic chloride water
repellent, or the like may be used. For enhancing absorbability of menstrual blood
or the like at the wing W, a hydrophilically treated nonwoven fabric may be used as
the material of the nonwoven fabric. A preferable type of the nonwoven fabric is an
air-through nonwoven fabric that is less likely to develop folds, wrinkle-resistant,
and soft.
[0022] On the outer edge of the wings W, W, for the purpose of bonding the side nonwoven
fabric 7 and the backsheet 2, and increasing rigidity, dotted compressed portions
(embosses) or a compressed portion with a predetermined shape may be provided in a
predetermined area.
[0023] The total length of the absorbent article 1 may be 130 to 450 mm, and also may be
200 to 360 mm.
[0024] The absorbent article 1 includes a compressed groove (also referred to as pressed
groove, or emboss). The compressed groove is formed so as to be a linear groove recessed
from the topsheet 3 side to the backsheet 2 side. The compressed groove functions
to prevent the absorbent body 4 from being twisted, to control body fluid migration
on the surface or in the inside of the absorbent body, and to facilitate an appropriate
deforming following the shape of the body. The compressed groove may be formed by
passing a stack including the absorbent body 4 and the topsheet 3 thereon between
a pair of pressing rolls. For example, the stack may be let through so that a protruded
roll is arranged on the topsheet 3 side and a planar roll is arranged on the absorbent
body 4 side.
[0025] As shown in FIG. 1, the compressed groove includes a pair of front-rear direction
grooves 10, 10 extending in the front-rear direction, line-symmetrically with respect
to a front-rear direction centerline CL of the main body. The pair of front-rear direction
compressed grooves 10, 10 may extend in the front-rear direction, along the lateral
sides of the body fluid discharge opening corresponding portion 40, or through a position
laterally away from the body fluid discharge opening corresponding portion 40 by a
predetermined distance, so that the grooves 10, 10 are not on the portion corresponding
to the body fluid discharge opening such as the vaginal opening when attached (the
body fluid discharge opening corresponding portion) 40. The length of the front-rear
direction compressed grooves 10, 10 may be approximately 50 to 85 % with respect to
the length of the main body. Further, the front-rear direction compressed grooves
10, 10 may extend linearly as a whole, or may be curved in mid-course as shown in
the illustrated example. A pair of front-rear direction grooves 10, 10 is not necessarily
line-symmetric. The paired front-rear direction grooves 10, 10 are preferably respectively
provided on each side of the front-rear direction centerline CL.
[0026] The pair of front-rear direction compressed grooves 10, 10 may function as base points
(flexible shafts) at which the absorbent article main body 8 can be easily bent. Therefore,
when forces of both legs are applied from lateral sides (in the direction orthogonal
to front-rear direction) toward the main body 8, the front-rear direction compressed
grooves 10, 10 can become base points for raising the region between the front-rear
direction compressed grooves 10, 10. Accordingly, the fittability of the main body
8 to the human body can be enhanced.
[0027] A pair of front-rear direction compressed grooves 10, 10 includes high-compressed
portions 11, and a low-compressed portion 12 that is less deeply depressed than in
a high-compressed portions 11 (FIGs. 1 and 2) . In the drawings, the high-compressed
portions 11 are illustrated in black, and the low-compressed portion 12 is illustrated
in white (with no coloring). The compression depths of the high-compressed portions
11 and the low-compressed portion 12 are not particularly limited, but the high-compressed
portions 11 are formed to have a depth approximately 0.5 mm to 3 mm deeper than the
bottom surface of the low-compressed portion 12. Further, in the front-rear direction
compressed grooves 10, 10, the high-compressed portions 11 may be continuously or
discontinuously formed in the front-rear direction. Preferably, the high-compressed
portions 11 are discontinuously formed in the front-rear direction (the plurality
of the high-compressed portions 11 are separated with each other in the front-rear
direction), so that the grooves have an appropriate rigidity. Such structure of the
compressed groove including the high-compressed portions and the low-compressed portion
may be obtained by using pressure rolls having recesses and protrusions corresponding
to a desired structure. For example, the pressure roll may be configured to have projections
corresponding to the entire shape of the compressed grooves, and fine protrusions
corresponding to the shape of the high-compressed portions on the projections. Alternatively,
the low-compressed portions may be firstly formed at a relatively low pressure in
the region where the compressed grooves are to be formed, and then the high-compressed
portions may be formed partially in the region of the low-compressed portions. The
depth of the compressed portions may be controlled by adjusting the pressure of the
above-mentioned pressure rolls used for forming the compressed grooves.
[0028] In the present embodiment, the high-compressed portions and the low-compressed portion
may be formed also in the compressed grooves other than the front-rear direction compressed
grooves 10, 10. In the example illustrated in FIG. 1, the high-compressed portions
and the low-compressed portion are formed in all compressed grooves including later-described
front compressed groove 20.
[0029] In the example illustrated in FIG. 1, a pair of the front-rear direction compressed
grooves 10, 10 includes middle compressed grooves 10a, 10a, first rear compressed
grooves 10b, 10b, and second rear compressed grooves 10c, 10c, which may be connected
in the stated order in the front-rear direction. The middle compressed grooves 10a,
10a are formed in the middle region A, the first rear compressed grooves 10b, 10b
are formed in the first rear region B, and the second rear compressed grooves 10c,
10c are formed in the second rear region C.
[0030] The length in the front-rear direction of the middle compressed grooves 10a, 10a
may be 60 to 110 mm, the length in the front-rear direction of the first rear compressed
grooves 10b, 10b may be 30 to 60 mm, and the length in the front-rear direction of
the second rear compressed grooves 10c, 10c may be 30 to 60 mm.
[0031] The middle region A includes the body fluid discharge opening corresponding portion
40, and may substantially correspond to a part from the urethral opening to the anus
between the legs of the wearer when attached. Further, the first rear region B is
the region corresponding to the intergluteal cleft of the wearer, more specifically,
the region extending in the front-rear direction and including a part corresponding
to the wearer's intergluteal cleft (intergluteal cleft corresponding region). The
first rear region B may be a region covering the whole gluteal cleft, or a region
corresponding to a part from a rear part of the perineum or the vicinity thereof,
or from anus or the vicinity thereof to the lower end of tailbone or the vicinity.
The second rear region C may substantially be a region from a position corresponding
to a rear end of gluteal cleft to the rear end of the main body 8. The region forward
of the middle region A may be a front region F.
[0032] As described above, when the main body 8 receives a force from the legs while being
attached, the front-rear direction compressed grooves 10, 10 usually become base edges
so that the region between the front-rear direction compressed grooves 10, 10 of the
main body 8 can be highly raised. The highly raised region between the front-rear
direction compressed grooves 10, 10 may usually be well fitted to a relatively narrow
deep groove in crotch.
[0033] However, the intergluteal cleft is wider and less deep than the cleft in the crotch.
Accordingly, in a case that the region between the front-rear direction compressed
grooves 10, 10 is sharply raised, the main body 8 may not be well tightly fitted to
the intergluteal cleft.
[0034] In light of the above, according to an example of the present invention, the pair
of the front-rear direction compressed grooves 10, 10 includes the first rear compressed
grooves 10b, 10b formed in a region B corresponding to the intergluteal cleft of the
wearer when attached, and the middle compressed grooves 10a, 10a formed forward of
the first rear compressed grooves 10b, 10b. Further, a total area per unit length
Sb of all the high-compressed portions 11 of the first rear compressed grooves 10b,
10b in the front-rear direction is smaller than a total area per unit length Sa of
the high-compressed portions 11 of the middle compressed groove 10a, 10a in the front-rear
direction (Sb < Sa).
[0035] In the present specification, the "total area per unit length in the front-rear direction
of the high-compressed portions" means a total area of all the high-compressed portions
11 within a region between two imaginary lines extending across the main body 8 in
the width direction at a predetermined distance with each other. For example, the
total area of all the high-compressed portions included within a region between two
imaginary lines at a distance of 3 cm in the front-rear direction from each other
may be calculated for each of the compressed grooves (for the middle compressed grooves
10a, 10a, and the first rear compressed grooves 10b, 10b), and each calculated total
area may be compared. Further, the total areas calculated either on the left half
side or the right half side of the front-rear direction centerline CL may be compared.
[0036] As the high-compressed portions 11 are portions intensively and deeply compressed
by pressure rolls as described above, the smaller the area of the high-compressed
portions 11 per unit length is, the less rigid the compressed groove becomes. Therefore,
the rigidity of the first rear compressed grooves 10b, 10b is lower than the rigidity
of the middle compressed grooves 10a, 10a, and thus the surrounding area of the first
rear compressed grooves 10b, 10b is also less rigid. With this configuration, the
first rear region B can be kept soft, allowing the main body 8 not to bend sharply
at the first rear compressed grooves 10b, 10b as base points . Accordingly, the main
body 8 can be well deformed following the shape of the intergluteal cleft, which is
wider and less deep than the cleft in the crotch.
[0037] The ratio of the total area Sb per unit length in the front-rear direction of the
high-compressed portions 11 in the first rear compressed grooves 10b, 10b to the total
area Sa per unit length in the front-rear direction of the high-compressed portions
11 in the middle compressed grooves 10a, 10a (Sb/Sa) may be preferably 0.2 to 0.6,
more preferably 0.32 to 0.52.
[0038] The function and effect of the structure of the compressed grooves according to the
present example will be further described referring to FIG. 3A and 3B. FIG. 3A is
a cross-sectional view showing how the main body 8 is contacted with the buttocks
70 when the absorbent article 1 in Fig. 1 is attached. On the other hand, FIG. 3B
is a cross-sectional view showing how the main body 8' according to the prior art
is contacted with buttocks cleft 70.
[0039] In FIG. 3B, the compressed grooves 10b', 10b' formed in the first rear region B of
the conventional absorbent article main body 8' has the same structure and the same
rigidity as the middle compressed grooves formed forward of the compressed grooves
10b', 10b'. Therefore, the main body 8' can be easily sharply bent at the compressed
grooves 10b', 10b' as base points, and the region between the compressed grooves 10b',
10b' may likely be protruded and highly raised. Accordingly, the main body 8' cannot
be well fitted to the shape of the wider cleft 70 of the buttocks, and a gap is likely
formed between the buttocks and the main body 8', which may result in leakage of body
fluid.
[0040] In the present example, the first rear compressed grooves 10b, 10b provided in the
first rear region B of the absorbent article main body 8 have a different structure
from the middle compressed grooves 10a, 10a formed forward of the first rear compressed
grooves 10b, 10b (FIG. 1). Specifically, the total area Sb per unit length in the
front-rear direction of the high-compressed portions 11 in the first rear compressed
grooves 10b, 10b is lower than the total area Sa per unit length in the front-rear
direction of the high-compressed portions 11 in the middle compressed grooves 10a,
10a, and thus the rigidity of the first rear compressed grooves 10b, 10b is smaller
than the rigidity of the middle compressed grooves 10a, 10a. Therefore, the first
rear compressed grooves 10b, 10b are not bent sharply, and the softness of the main
body 8 as a whole can be maintained. The main body 8 is gently raised as shown in
FIG. 3A, and is fitted along the shape of the intergluteal cleft 70. Accordingly,
the leakage of the body fluid, especially the rearward leakage along the intergluteal
cleft 70 can be prevented.
[0041] A distance between the first rear compressed grooves 10b, 10b is smaller than a distance
between the middle compressed grooves 10a, 10a. With this configuration, the height
of the raised region of the main body 8 in the first rear region B can be lower than
in the middle region A, so that the first rear region B can be well fitted to the
buttocks.
[0042] Further, since the softness of the main body 8 can be maintained in the region B
corresponding to the intergluteal cleft as described above, the main body 8 can be
deformed following the change of the width or the depth of the intergluteal cleft
when the position of the human body is changed. Moreover, the middle compressed grooves
10a, 10a are connected to the first rear compressed grooves 10b, 10b, resulting in
a good fittability to a transition part from the crotch part to the intergluteal cleft
of the wearer. Therefore, the absorbent article 1 according to the present example
can well prevent the rearward leakage even for a long time or during a sleeping time,
and thus is preferably used as a sanitary napkin for long time-use or for sleeping
time-use.
[0043] In the example shown in FIG. 1, as described above, a pair of the front-rear direction
compressed grooves 10, 10 includes the middle compressed grooves 10a, 10a, the first
rear compressed grooves 10b, 10b, and additionally the second rear compressed grooves
10c, 10c. A total area Sc per unit length in the front-rear direction of high-compressed
portions in the second rear compressed grooves 10c, 10c may be greater than the total
area Sb per unit length in the front-rear direction of the high-compressed portions
in the first rear compressed grooves 10b, 10b (Sc > Sb). Therefore, the rigidity of
the second rear compressed grooves 10c, 10c, which is closer to the rear end, can
be higher than in the first rear compressed grooves 10b, 10b. Accordingly, twists
and wrinkles are prevented in the second rear region C, which faces the part in which
only a narrow or no intergluteal cleft exists, while maintaining the above-described
effect that the rigidity in the first rear region (intergluteal cleft corresponding
region) B can be lowered to maintain the softness of the main body, and the main body
can be well deformed following the shape of the intergluteal cleft.
[0044] The ratio of the total area Sc per unit length in the front-rear direction of the
high-compressed portions in the second rear compressed grooves 10c, 10c to the total
area Sb per unit length in the front-rear direction of the high-compressed portions
in the first rear compressed grooves 10b, 10b (Sc/Sb) is preferably 1 to 4.5, more
preferably 1.5 to 3.5.
[0045] The total area Sc per unit length in the front-rear direction of the high-compressed
portions in the second rear compressed grooves 10c, 10c may be the same as or different
from the total area Sa per unit length in the front-rear direction of the high-compressed
portions in the middle compressed grooves 10a, 10a.
[0046] In the illustrated example, the second rear compressed grooves 10c, 10c are more
curved inwardly and have a shorter distance between the compressed grooves in the
rear direction, to be connected with each other at the rear end. However, the shape
in planar view of the second rear compressed grooves 10c, 10c is not limited to the
illustrated example, and the second rear compressed grooves 10c, 10c may not necessarily
be connected with each other.
[0047] FIGs. 4A to 4C are enlarged views of part I, II, and III in FIG. 1, i.e., partially
enlarged views of the middle compressed grooves 10a, 10a, the first rear compressed
grooves 10b, 10b, and the second rear compressed grooves 10c, 10c, respectively. As
illustrated, each of the compressed grooves has the high-compressed portions 11 and
the low-compressed portion 12.
[0048] Further, as shown in FIG. 4A and FIG. 4B, a groove width w
b of the first rear compressed groove 10b is preferably less than a groove width w
a of the middle compressed groove 10a (w
b < w
a). Therefore, the rigidity of the first rear compressed groove 10b can be further
lowered, thereby enhancing the function and the effect that the softness of the main
body 8 can be maintained in the first rear region B.
[0049] The groove width w
b of the first rear compressed groove 10b is preferably 0.5 to 3.0 mm, and more preferably
1 to 2 mm. The groove width w
a of the middle compressed groove 10a is preferably 1.0 to 3.5 mm, and more preferably
1.5 to 2.5 mm. The ratio of the w
b to the w
a (w
b/w
a) is preferably 0.60 to 0.9, and more preferably 0.65 to 0.85.
[0050] Further, as illustrated, a pitch p
b of the high-compressed portions 11 in the first rear compressed groove 10b is preferably
greater than a pitch p
a of high-compressed portions 11 in the middle compressed groove 10a (p
b > p
a). Therefore, the area of the low-compressed portion 12 can be decreased in the first
rear compressed groove 10b, thereby enhancing the function and effect that the rigidity
of the first rear region B can be lowered and the softness of the main body 8 can
be maintained in the first rear region B.
[0051] The pitch p
b of the high-compressed portions 11 in the first rear compressed groove 10b is preferably
4 to 10 mm, and more preferably 6 to 8 mm. The pitch p
a of the high-compressed portions 11 in the middle compressed groove 10a is preferably
2.5 to 6 mm, and more preferably 3.4 to 4.4 mm. The ratio of the p
b to the p
a (p
b/p
a) is preferably 1.2 to 2.8, and more preferably 1.3 to 2.3.
[0052] A distance d
b between the high-compressed portions 11 in the first rear compressed groove 10b is
also preferably greater than a distance d
a between the high-compressed portions 11 in the middle compressed groove 10a (d
b > d
a). The distance d
b between the high-compressed portions 11 in the first rear compressed groove 10b is
preferably 2.5 to 7 mm, more preferably 3.5 to 6.5 mm. Further, the distance d
a between the high-compressed portions 11 in the middle compressed groove 10a is preferably
0.5 to 3 mm, more preferably 1.2 to 2.3 mm.
[0053] As illustrated, a groove width w
c of the second rear compressed groove 10c is preferably greater than a groove width
w
b of the first rear compressed groove 10b (w
c > w
b). This allows the rigidity of the second rear region C to be greater than the rigidity
of the first rear region B. Therefore, the above-described effect to lower the rigidity
of the first rear region B and to maintain the softness of the main body 8, enabling
a deformation of the main body well following the shape of the intergluteal cleft,
is achieved, and twists and wrinkles in the second rear region C closer to the rear
end can be prevented.
[0054] A groove width w
c of the second rear compressed groove 10c is preferably 1.0 to 3.5 mm, more preferably
1.5 to 2.5 mm. Further, the ratio of the w
c to the w
b (w
c/w
b) is preferably 1.1 to 1.5, more preferably 1.2 to 1.4. The groove width w
c of the second rear compressed groove 10c may be the same as the groove width w
a of the middle compressed groove 10a.
[0055] Further, a pitch p
c of the high-compressed portions 11 in the second rear compressed groove 10c is preferably
smaller than a pitch p
b of the high-compressed portions 11 in the first rear compressed groove 10b (p
c < p
b). This allows the rigidity of the second rear region C to be greater than the rigidity
of the first rear region B. Therefore, the above-described effect to lower the rigidity
of the first rear region B and to maintain the softness of the main body 8, enabling
the main body to be well deformed following the shape of the intergluteal cleft, can
be achieved, and the twists and the wrinkles in the second rear region C closer to
the rear end can be prevented.
[0056] A pitch p
c of the high-compressed portions 11 in the second rear compressed groove 10c is preferably
3.5 to 7.5 mm, more preferably 4.5 to 6.5 mm. Further, the ratio of the p
c to the p
b (p
c/p
b) is preferably 0.5 to 0.9, more preferably 0.68 to 0.88. The pitch p
c of the high-compressed portions 11 in the second rear compressed groove 10c may be
the same as the pitch p
a of the high-compressed portions 11 in the middle compressed groove 10a.
[0057] Further, a distance d
c between the high-compressed portions 11 in the second rear compressed groove 10c
is preferably smaller than the distance d
b between the high-compressed portions 11 in the first rear compressed groove 10b (d
c < d
b). The distance d
c between the high-compressed portions 11 in the second rear compressed groove 10c
is preferably 2.5 to 5 mm, more preferably 3 to 4.5 mm.
[0058] The above-mentioned groove widths w
a, w
b, and w
c each may be constant or vary along the compressed groove. Further, the pitches p
a, p
b, and p
c, and the distances d
a, d
b, and d
c each may also be constant or vary along the compressed groove. When the pitch or
the distance varies along the compressed groove, the p
a, p
b, p
c, d
a, d
b, or d
c may be an averaged value in each compressed groove.
[0059] In the illustrated example, in the front-rear direction compressed grooves 10, 10,
the high-compressed portions are formed to contact with one of the edges of the compressed
groove. Specifically, a high-compressed portion contacted with the one edge of the
compressed groove and a high-compressed portion contacted with the other edge of the
compressed groove are alternately arranged to form a staggered arrangement. The staggered
arrangement is preferred, because it allows the high-compressed portions to be formed
with certainty in the fabrication. However, the arrangement of the high-compressed
portions is not limited to the illustrated embodiment, and the high-compressed portions
may be each formed to contact with both edges of the compressed groove and arranged
at a predetermined distance.
[0060] Further, the shape of the high-compressed portion in the front-rear direction compressed
groove 10, 10 is a half circle in FIG. 1, but may be a circle, an ellipse, a polygon
such as a quadrangle. In any of the above cases, the high-compressed portions may
be formed to contact with both edges of the compressed groove, or to contact with
one of the edges of the compressed groove. For example, as in the later described
front compressed groove 20, the high-compressed portion may be formed in a circular
shape contacting with both edges of the compressed groove. Further, the high-compressed
portions may be arranged contacting with neither edge of the compressed groove.
[0061] As shown in FIG. 1, the compressed groove may include the front compressed groove
20. With the configuration including the front compressed groove 20, the front region
can be easily curved following the roundness of the human body, and prevent the leakage
from the front side.
[0062] The shape of the front compressed groove 20 is also not particularly limited. However,
a shape including a V-shape, such as a heart shape as in the illustrated example,
is preferred, because the tip of the V-shape can be a base point for deforming the
front region to be curved.
[0063] FIG. 5 shows an absorbent article 501 according to another example. Likewise in the
example illustrated in FIG. 1, the absorbent article 501 includes a main body 508,
and a compressed groove recessed from a topsheet 503 side toward a backsheet side.
The compressed groove includes front-rear direction compressed grooves 510, 510, the
front-rear direction compressed grooves 510, 510 including middle compressed grooves
510a, 510a and first rear compressed grooves 510b, 510b. However, the absorbent article
501 may differ from the absorbent article 1 shown in FIG. 1, in that the front-rear
direction compressed grooves 510, 510 do not include second rear compressed grooves,
but include a width direction rear compressed groove 530 in the second rear region
C. Further, the length of the absorbent article 501 is shorter than the length of
the absorbent article 1 by shortening the length of the second rear region C.
[0064] Also in the example shown in FIG. 5, in a plane view, a total area per unit length
in the front-rear direction of high-compressed portions 511 in the first rear compressed
grooves 510b, 510b is smaller than a total area per unit length in the front-rear
direction of the high-compressed portions 511 in the middle compressed grooves 510a,
510a. Therefore, while maintaining the fittability in the middle region A, which corresponds
to a crotch part of the wearer when attached, the rear first compressed region B,
i.e., the intergluteal cleft corresponding region can be kept soft, thereby improving
the fittability of the rear first compressed region B to the intergluteal cleft.
[0065] The width direction rear compressed groove 530 may also include high-compressed portions
and a low-compressed portion. A width, a pitch of the high-compressed portions, or
a distance between the high-compressed portions of the width direction rear compressed
groove 530A may be the same as or different from those in the first rear compressed
grooves 510b, 510b, and further be the same as or different from in the middle compressed
grooves 510a, 510a.
[0066] Preferred embodiments of the present invention are described below as appendices.
(Appendix 1)
[0067] An embodiment according to Appendix 1 provides an absorbent article that includes
a main body including a liquid-permeable topsheet, a liquid-impermeable backsheet,
and an absorbent body disposed between the topsheet and the backsheet, wherein the
main body has an elongated shape with a predetermined length in the front-rear direction
and a predetermined width in a width direction orthogonal to the front-rear direction,
and includes a compressed groove recessed from a topsheet side toward a backsheet
side, wherein the compressed groove includes a pair of front-rear direction compressed
grooves extending in the front-rear direction, wherein the front-rear direction compressed
grooves each include high-compressed portions and a low-compressed portion that is
less deeply recessed than the high-compressed portions, and includes a first rear
compressed groove formed in a region corresponding to an intergluteal cleft of a wearer
when attached, and a middle compressed groove formed forward of the first rear compressed
groove, and wherein a total area per unit length in the front-rear direction of the
high-compressed portions in the first rear compressed groove is smaller than a total
area per unit length in the front-rear direction of the high-compressed portions in
the middle compressed groove.
[0068] In the embodiment according to Appendix 1, the front-rear direction compressed groove
includes the first rear compressed groove formed in the region corresponding to an
intergluteal cleft of the wearer when attached, and the middle compressed groove formed
forward of the first rear compressed groove. Further, the total area per unit length
in the front-rear direction of the high-compressed portions in the first rear compressed
groove is smaller than the total area per unit length in the front-rear direction
of the high-compressed portions in the middle compressed groove. Therefore, the rigidity
of the region corresponding to the intergluteal cleft (the intergluteal cleft corresponding
region), in which the first rear compressed groove is formed, can be lower than the
rigidity of the middle region of the main body, in which the middle compressed groove
is formed. This allows for maintaining the softness of the main body in the region
corresponding to the intergluteal cleft, and for deforming the main body well following
the shape of the intergluteal cleft. As a result, the absorbent article can be well
fitted to the intergluteal cleft, with no gap between buttocks and the main body,
thereby preventing rearward leakage of body fluid.
(Appendix 2)
[0069] An embodiment according to Appendix 2 provides that a groove width of the first rear
compressed groove is smaller than a groove width of the middle compressed groove.
[0070] In the embodiment according to Appendix 2, the decreased width of the rear compressed
groove can lower the rigidity attributed to the first rear compressed groove. Therefore,
the rigidity of the main body in the intergluteal cleft corresponding region can be
lowered, enhancing the effect that the main body can be well deformed following the
shape of the intergluteal cleft.
(Appendix 3)
[0071] An embodiment according to Appendix 3 provides that a pitch of the high-compressed
portions in the first rear compressed groove is greater than a pitch of the high-compressed
portions in the middle compressed groove.
[0072] In the embodiment according to Appendix 3, the greater pitch of the high-compressed
portions in the first rear compressed groove can lower the rigidity attributed to
the first rear compressed groove. Therefore, the rigidity of the main body in the
intergluteal cleft corresponding region can be lowered, enhancing the effect that
the main body can be well deformed following the shape of the intergluteal cleft.
(Appendix 4)
[0073] An embodiment according to Appendix 4 provides that the front-rear direction compressed
grooves each include a second rear compressed groove formed backward of the first
rear compressed groove, and a total area per unit length in the front-rear direction
of the high-compressed portions in the second rear compressed groove is greater than
the total area per unit length in the front-rear direction of the high-compressed
portions in the first rear compressed groove.
[0074] In the embodiment according to Appendix 4, the front-rear direction compressed grooves
each include the second rear compressed groove rearward of the first rear compressed
groove, and the total area of the high-compressed portions in the second rear compressed
groove is greater than the total area of the high-compressed portions in the first
rear compressed groove, per unit length in the front-rear direction. With this configuration,
the rigidity of a further rear region rearward of the intergluteal cleft corresponding
region, i.e., the region in which the second rear compressed groove is provided, can
be higher than the rigidity of the intergluteal cleft corresponding region. Therefore,
twists and wrinkles can be prevented in the region closer to the rear end, while maintaining
the effect that the rigidity in the intergluteal cleft corresponding region can be
lowered to maintain the softness of the main body, and thus the main body can be well
deformed following the shape of the intergluteal cleft.
(Appendix 5)
[0075] An embodiment according to Appendix 5 provides that a groove width of the second
rear compressed groove is greater than a groove width of the first rear compressed
groove.
[0076] In the embodiment according to Appendix 5, the greater groove width of the second
rear compressed groove can enhance the rigidity of the region rearward of the intergluteal
cleft corresponding region, closer to the rear end. Therefore, twists and wrinkles
in the region rearward of the intergluteal cleft corresponding region can be prevented,
while maintaining the effect that the main body can be well deformed following the
shape of the intergluteal cleft in the intergluteal cleft corresponding region.
(Appendix 6)
[0077] An embodiment according to Appendix 6 provides that a pitch of the high-compressed
portions in the second rear compressed groove is smaller than the pitch of the high-compressed
portions in the first rear compressed groove.
[0078] In the embodiment according to Appendix 6, the reduced pitch in the second rear compressed
groove can increase the rigidity in the region rearward of the intergluteal cleft
corresponding region, closer to the rear end. Therefore, twists and wrinkles in the
region rearward of the intergluteal cleft corresponding region can be prevented, while
maintaining the effect that the main body can be well deformed in the intergluteal
cleft corresponding region following the shape of the intergluteal cleft.
[0079] The present application is based on and claims benefit of priority of Japanese Patent
Application No.
2017-119742, filed June 19, 2017, the entire contents of which are hereby incorporated herein by reference.
Reference Signs List
[0080]
1, 501 absorbent article
2 backsheet
3, 503 topsheet
4 absorbent body
5 enveloping sheet
7 side nonwoven fabric
8, 508 main body (absorbent article main body)
10, 510 front-rear direction compressed groove
10a, 510a middle compressed groove
10b, 510b first rear compressed groove
10c second rear compressed groove
11, 511 high-compressed portion
12, 512 low-compressed portion
20 front compressed groove
40 body fluid discharge opening corresponding portion
70 intergluteal cleft
530 width direction rear compressed groove
CL front-rear direction centerline
A middle region
B first rear region (intergluteal cleft corresponding region)
C second rear region
F front region
W wing